Electrolytic cell



Dec. M i923. 114775'112 n R. H. MCKEE ELECTROLYTIC CELL Original Filed Sept. 4. 1919 Patented Der, ill, 1923,

inn/na RALPH H. MCKEE, OF NEW YORK, N. Y.

ELECTROLYTIC CELL.

@riginal-application filed September e, 1919, Serial No. 321,609. Divided and this application led october 13, 1920.

To all whom it may concern.

Be it known that ll RALPH H. MCKEE, a

citizen of the United tates, residing at New York, in the county of New York and State of New `York, have invented certain new and useful Tm `rovements in Electrolytic Cells, of which t e following is a specification.

This invention is a novel electrolytic cell of the dia hragm type, intended more par- Hl ticularly or -use in `connection with such electrolytic operations as involve either an oxidation or a reduction of solutions; a typical exam le of such operations being the oxidation of) acid solutions containing a salt of l chromium, as disclosed in my copending application Serial Number 321,609, tiled September 4, 1919, of which the present case is a division.

A characteristic feature of the present invention consists .in the provision in a cell of the diaphragm type of means for establishing a deinite flow of the electrolyte past the respective electrodes, in conjunction with means for augmenting the flow of electrolyte ast one of these electrodes. ln the preerred embodiment of the invention the electrolyte as a Whole flows in opposite directions past opposed, parallel electrodes separated by a porous diaphragm. When the cell is .im used for oxidizing reactions of the nature mentioned above the anode area is preferably substantially in excess of that of the cathode: and the increased volume of flow per unit of time occurs in the anode compartment. For

reducin reactions these conditions may be reverset An illustrative embodiment of the invention is shown in the accompanying drawing wherein the figure is a plan view of an eo electrolytic cell designed for continuous flow.

ln the figure -10 represents the electrolytic cell, and 11 a porous cup or compartment which functions as .an electrolytic diaphragm. This diaphragm may be made of any porous material not a'ected by the solutions used: for instance, for acid solutions, as in the chromic salt oxidation mentioned above, it is best constructedfrom a porous.

Serial No. 413,651.

the porous cup, the e'ective anode area being as shown much in excess of that of the cathode or cathodes. 14 represents the inlet for the electrolyte, its flow through the cell being as indicated by the arrows; that is to say past the electrode 12, thence into the outer compartment through pipe 15 (in addition to any outflow through the Walls of the porous vessel 11) thence pastthe electrodes 13,' 13 in a direction opposite to that of its iow past electrode 12, and finally out of the electrolytic field through a Siphon or other discharge pipe 16.

17 represents a supplemental inlet for elec'- trolyte, supplying the same directly to the outer compartment, which inthe particular case under consideration is the anode compartment.

When the cell is used for the anodic oxidation of chromium salts the level of liquid in the cathode compartment (that is to say, Within the porous cup in thetype of apparatus chosen for illustration) is maintalned Asomewhat above that in the outer cell, with the result that there is at all times some outward the active faces of the anodes. This lHow is also indicated by arrows in the figure. The obj ect to be obtained by providing means for augmenting the volume of electrolyte Howing through one compartment as compared with the volume flowing in the same unit period through the other compartment can best be explained by reference to a specific example, such for example as vthe oxidation of chromium salts mentioned above.

lt will be understood by those familiar with this art that the primary function of the cell is to oxidize chromium sulfate into chromic acid, and that this oxidation takes place at or near the active anode faces: at the same time the concentration of sulfuric acid tends to increase in the region of the anodes and to diminish in the region of the cathode. Tt is essential however that a sufficient acid concentration should be at all times maintained at the cathode, since otherwise a deposition of chromic hydroxid may occur with resulting clogging of the diaphragm. According to my invention the acid concentration at the cathode is maintained by the direct supply at that point, that is to say through inlet 14, of a sufficient quantity of raw liquor, which always contains free sullll@ furie acid. Since, however, the effective work of the cell is done at the anodes, it is desirable to limitI the supply of raw liquor to the cathode compartment to the volume necessary for maintaining the desired acid concentration. Hence I provide the supplemental inlet 17 for raw liquor, supplying the same direct-ly to the anode compartment as described above.

Obviously numerous changes may be made in the form or manner of assembly of the cell without departing from my invention.

I claim 1. In an electrolytic cell, the combination with an anode and a cathode, of a porous diaphragm separating the same; means for establishing a definite flow of the electrolyte successively past said electrodes; and means for augmenting the volume of electrolyte flowing in unit time past one of said electrodes 2. In an electrolytic cell, the combination l with an anode and a cathode, of a porous diaphragm separating the same; means for establishing a deiinite flow of the electrolyte successively past said electrodes in opposite directions; and means for augmenting the volume of electrolyte flowing in unit time past one of said electrodes.

3. In an electrolytic cell, the combination with a porous vessel and a container therefor; of electrodes located respectively inside and outside of said orous vessel; means for establishing a defimte flow of the electrolyte.

successively past said electrodes; and means for augmenting the volume of the electrolyte flowing in unit time past the outer electrodes.

4. In an electrolytic cell, the combination with a porous vessel and a container therefor; of electrodes located respectively inside and outside of said porous vessel; means for establishing a definite flow 'of the electrolyte successively past said electrodes in opposite directionsand means for augmenting the volume o the electrolyte flowing in unit time p-ast the outer electrodes.

In testimony whereof, I aiiix m si ature.

RALPH H. 

